<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>延迟显示元素</title>
</head>
<body>
<div id="change" class="change">
  <h1>Hello, World!</h1>
</div>

<script>
  let element = document.querySelector("#change");

  // setTimeout(()=>{
  //     element.innerHTML = " <h1>Hello, World!</h1> <h1>Hello, Vue!</h1>"
  // }, 3000)



  let item = document.createElement("h1");
  item.innerText = "Hello, Vue!"

  setTimeout(function () {
      element.appendChild(item)
  }, 3000)


</script>
</body>
</html>